23 Fran asks each of 40 students how many books they bought last year.
The chart below shows information about the number of books bought by each of the 40 students.
Number of
students
14-
12
10
8
9
4
2
0 to 4
5 to 9
10 to 14
15 to 19 20 to 24
Number of books
(a) Work out the percentage of these students who bought 20 or more books.